Thread cutter for automatic looms



April 7, 1942.

E. P. G UERIN THREAD CUTTER FOR AUTOMATIC LOOMS Filed April 21, 1941 2-Sheets-Sheet l 1NVEN'TOR. ERNEST P Susana QRNEY A ril 7, 1942. E. P.GUERlN 2,278,545

THREAD CUTTER FOR AUTOMATIC LOOMS Filed April 21, 1941 2 SheetS-Sheet 2FIE-E INVENTQR ERN EST P. Gov-42x N ATTORNEY ?atented Apr. 7, 1942 I2,278,546 THREAD CUTTER ron AUToMATrq ooMs Ernest P. Guerin, Lawrence,Mass., .assignor to Crompton & Knowles Loom Works, Worcester, ,Mass" acorporation of Massachusetts Application April 21, 1941, Serial No.389,576

7 Claims.

This invention relates to thread cutters for automatic looms and it isthe general object, of the invention to provide a cutter for severingthe thread of the outgoing bobbin without cutting the thread extendingfrom the adjacent selvage to a shuttle boxed under the magazine.

In weft replenishing mechanisms more particularly of the pick and picktype it is customary to replenish one shuttle while another shuttle islocated on the same side of the loom as the replenishing mechanism. Thethread of the outgoing bobbin must be severed to prevent it from beingdrawn into the shed by the active shuttle, but the thread leadingfrom'the selvage to the other shuttle must remain intact so that whencalled into action said other shuttle can weave properly. Weftreplenishing mechanisms are ordinarily provided with a clamp which holdsthe thread of the outgoing bobbin in forward position after transferwhile the thread to the other bobbin moves backwardly with the lay in adirection away from the thread held by the clamp. It is an importantobject of my present invention to provide a thread cutter operated bybackward motion of the lay and having a zone of operation which liesbehind the thread of the outgoing bobbin but in front of the threadextending to the boxed shuttle.

It is a further object of my present invention to provide a threadcutter normally in forward position but movable toward cutting positionalong a path having two components the first of which is rearwardagainst the thread to be cut to bend it and the second of which isupward so that the bent thread can snap forwardly to a position in frontof the cutter as the latter returns to forward position. These motionsof the cutter occur when the lay is in rearward position and thedownward motion occurs shortly'after the lay starts forwardly, hence thecutter descends in front of the thread extending to the boxed shuttleand remains in front'of that thread during continued advance of the lay.With these and other objects in view which will appear as thedescription proceeds, my invention resides in the combination andarrangement of parts hereinafter described and set forth. In theaccompanying drawings. wherein a convenient embodiment of my inventionis set forth,

Fig. 1 is a front elevation of part of a loom having my inventionapplied thereto,

Fig. 2 is a plan view taken in the direction of arrow 2, Fig. 1, withthe lay in rearward position,

Fig. 3 is an end elevation on an enlarged scale looking in the directionof arrow 3, Fig. 2,

Fig. :4 is an enlarged vertical section on line 4-4, Fig. 2 looking inthe direction opposite to that in which Fig. 3 is taken and showing thecutter at the completion of its opening stroke preparatory to a cuttingoperation,

Fig. 5 is a view similar to Fig. 4 but showing the parts restored tonormal position such as that existing when the lay approaches frontposition,

Fig. 6 is a rear elevation looking in the direction ofarrow 8, Fig. 3,and T Fig. '7 is a diagrammatic view similar to a portion of Fig. 2showing a bend produced in the clamped thread of the outgoing bobbin bythe cutter blade.-

Referring to the drawings, the loom frame it includes a breast beam llover which the fabric F passes. The lay L is provided with a reed Bthrough which the warp threads W extend. Mounted on the breast beam is atemple T having a rearwardly extending shank l2 with the usual burr podl3. The lay is provided with a protector rod ll of usual constructionfor a purpose to appear hereinafter.

' The right end of the lay is provided with a gang G of shuttle boxesincluding top and bottom cells l5 and I6, respectively, each having abinder I! which assists in holding shuttles in the cells. The upper andlower cells in the present instance are provided with shuttles S' andS2, respectively, and the boxes rise and fall with respect to the lay bymeans of mechanism not shown but operating through a box lifter rod 88.As shown in Fig. 1 the lower cell i6 with'its shuttle S2 is in; activeposition opposite the shuttle race 20, but it is to be understood thatthe boxes are shiftable downwardly so that the other shuttle S can alsobecome active.

The shuttle boxes are preferably controlled to call a plurality ofshuttles into action in a definite order or rotation so that threesuccessive picks will be laid by three different shuttles for thepurpose of mixing filling. Certain features of my invention however arenot limited to automatic looms of this particular type. When operatingas preferred, however, the shuttle box gang G will be up for two picksand then down for two picks, the boxes thereby having a cycle which iscompleted in four picks of the loom. when the boxes are down with ashuttle in the top cell, the shuttle will be picked to the left handside of the loom on the first pick of the repeat and on the second pickan-' other shuttle arriving from the opposite side of the loom willenter the top cell. The gang G then rises and a shuttle previouslystored in the lower cell is picked to the left side during the thirdpick, and during the fourth pick another shuttle arriving from the lefthand side will enter the lower cell. The boxes will then drop to startthe next cycle, and if replenishment has occurred in the top cell whilethe latter is raised as set forth in my co-pending application SerialNo. 365,093, there will be a thread 25 extending from the thread cutterdesignated generally at C to the adjacent selvage of the fabric, andthere will be also a second thread 28 extending from the selva'ge to theshuttle in the lower box cell l8 which is now inactive.

The thread cutter C 01 itself forms no part of my present invention andmay be of any approved form, such for instance as that shown in mypreviously mentioned application or in Patent No. 1,610,562. The threadcutter ordinarily moves to the forward position indicated in Fig. 1

after a replenishing operation so that thread will ordinarily extend tothe right and forwardly from the fell of the cloth regardless of theposition of the lay. The lay moves rearwardly immediately afterreplenishment to cause the thread 28 to be inclined to the right andrearwardly from the fell of the fabric. As shown in Fig. 2 there will bea considerable angle between the threads 25 and 28 when the lay is onback center position.

The magazine for effecting replenishment is not set forth herein and itis thought sufllcient for present purposes to state that the cutting bythe cutter C is effected at the time of replenishment and cutter C notonly cuts but also clamps the thread 25. It is necessary to cut thread25 adjacent to the selvage prior to the next replenishing operation ofthe loom to prevent this thread from being drawn into the shed and thuscausing a thick place in the fabric.

In carrying my present invention into effect I form the temple with ahead 38 the rear side of which is provided with the customary spacedvertical cutter blades 3|. Mounted for sliding motion in a vertical slot32 in the head is a cutter carrier 35 the rear end of which supports adownwardly extending blade 31 which may be shaped as shown in Fig. 4,for instance, with a rounded lower rear edge 38. The carrier is providedwith a slot 35 into which projects. a guide stud 48 threaded into thehead 38. A stud 4| projecting laterall from the head has secured theretoone end of a coil spring 42, the other end of which extends downwardlyas at 43 to be wrapped around a stud 44 on the carrier 25. The effect ofspring 42 is to move the carrier and cutter blade rearwardly, but thiseffect is normally nullified by a stronger spring 45 wrapped around astud 48 supported by the head 88 and having a depending arm 41 whichpasses behind a stud 48 secured to the carrier 35. The stud 48 is belowthe stud 44, while the springs and their studs may be locatedsubstantially'as shown in Figs. 4 and The lower end of arm 41 may beprovided with an eye 58 which receives leather .thong 5| the rear end ofwhich passes around the protector rod H. In the present instance I useth protector rod for convenience and it is to be understood that I amnot necessarily limited to this rod as a means for anchoring the rearend of the thong.

Under normal conditions when the lay is in the forward part of itsstroke the arm 41 presses on th stud 48 to move the carrier forwardlyagainst the action of spring 42. Under these conditions the force ofspring 42 is exerted through stud 44 above the stud 48 and the cutterblade and its carrier are thereby held in low position. As the lay movesrearwardly the thong is straightened and arm 41 starts to move to theright from the position shown in Fig. 5 toward the position shown inFig. 4, thus permitting spring 42 to move the slide rearwardly. As longas both springs exert their forces on th carrier the latter will moverearwardly in a substantially horizontal line, but as the lay continuesits rearward motion arm 41 will movebackwardly away from stud 48, thusleaving the spring 42 in control of the carrier 35. During backwardhorizontal motion of the carrier, surface 38 of blade 31 engages thread25 to produce a bend 52 in it, as indicated in Fig. 7.

The carrier 35 has a forward horn 55 provided with a rear normallyvertical surface 54 which engages the downwardly and rearwardly inclinededge 58 of the head 38 during backward motion of the lay, therebypreventing further substantial backward motion of the carrier 35, and itis for this reason that the arm 41 moves rearwardly away from the stud48 as the lay approaches its back center position. The head 30 isprovided with a downwardly and forwardly inclined surface 51, while thecarrier 25 has a normally horizontal surface 58 extending rearwardlyfrom the horn 55 and under surface 52 for engagement with the latter.Since stud 44 is below the horn 55 the latter tends to turn so that thesurface 54 will be aligned with the surface 58 on the head. This turningof the carrier can occur because of the normal relation of surfaces 51and 58, and also because of the sliding pivot provided by slot and pivotscrew 4|. As the carrier turns angularly to align surfaces 51 and 58,the blade 31 rises to a position above and to the rear of thread 25,reaching its highest position when the lay is on back center. Duringupward motion of blade 31 it rises to a point above thread 25 and thelatter snaps back to the position of Fig. 2 in front of blade 31.

As the lay starts to move forwardly th arm 41 moves forwardly toward theposition of Fig. 5, ultimately engaging stud 48 the first effect ofwhich is to rock the carrier 35 in a clockwise direction as viewed inFig. 4 to lower the blade 31 behind the thread 25, after which continuedforward motion of arm 41 as the lay advances causes horizontal forwardmotion of the carrier against the action of spring 42 until the blade 31cooperates with the blades 3| to cut the thread 25. The thong 5| willbecome slackened during forward motion of the lay after forward motionof the carrier 30 is arrested by engagement of pivot screw 40 with therear end of slot 39.

It will be noted from Fig. 2 that the downward 4 motion of the blade 31as the lay starts forwardly from its rearward position occurs whenthread 26 is behind the zone of operation of the cutter, and the springarm 4! acts to move the carrier 35 and the cutter blade forwardly infront of thread 28 as the latter approaches thread 25 with the advancinglay. The cutter is therefore always kept in a position well in advanceof thread 28 and the latter is in no danger of being cut.

From the foregoing it will be seen that I have provided a simple threadcutter which is set for operation by backward motion of the lay and hasits severing action during the first part of the forward motion of thelay when the thread 28 is out of the range of action of the cutter. Itwill further be seen that the cutter blade 37 descends along a pathbehind the thread 28 which it is to cut but in front of the thread 26which must remain intact. It will also be seen that the thread cutterhas a compound motion theflrst part of reciprocating between front andback center powhich is rearward and substantially horizontal to bendthread 25 at 52, and the second part of which is upward to open thecutter for action and permit the thread 25 to snap forwardly to aposition in front of cutter blade 31. On the actual cutting stroke thecutter traverses its opening path in reverse order and moves downwardlyto a osition behind thread 25 and then forwardly, being in front ofthread 26 at all times.

Having thus described my invention it will be seen that changes andmodifications may be made therein by those skilled in the art withoutdeparting from the spirit and scope of the invention and I do not wishto be limited to the details here-- in disclosed, but what I claim is: v

1. In a thread cutter for a loom having a lay reciprocating betweenfront and back center positions and provided with a thread extendingfrom a thread clamp to the adjacent salvage, a normally stationarysupport mounted in front of the lay having cutter means mounted thereon,a cutter mounted for backward and forward motion on the support, twoopposed springs one of which is stronger than the other and tendsnormally to hold the cutter in forward closed position relatively to thecutter means and the other of which tends to move the cutter to rearwardopen position relatively to the cutter means, a

stop to limit rearward motion of the cutter, and

sitions and provided with a thread extending from a thread clamp to theadjacent selvage, a normally stationary support mounted in front of thelay having cutter means mounted thereon. a cutter mounted on thesupport, means defining a sliding and rocking connection between thecutter and the support limiting rearward motion of the cutter, twosprings connected to the support and both actingon the cutter, one ofsaid springs being stronger than the other and acting to hold the cutterin forward closed position relatively to the cutter means and the otherspring tendingto move the cutter rearwardly toward said stop and to openposition relatively to the cutter means, and connections between the layand the stronger spring effective during rearward motion of the lay tomove the stronger spring rearwardly, whereupon the other spring movesthe cutter with a combined backward and upward rocking motion relativelyto the support to place the cutter behind the thread when the lay is inrear position, the stronger spring operative during the followingforward motion of the lay to move the cutter forwardly against theaction of said other sprlng'by a combined downward rocking and forwardlysliding motion relatively to the support from a point behind said firstthread to closed position relatively to the cutter means from a threadclamp to the adjacent selvage, a

normally stationary support mounted in front of the lay having cuttermeans mounted thereon. a cutter mounted on the support and having asubstantially horizontal slot therein, guide and 2. In athread cutterfor a loom having a lay reciprocating between front and back centerpositions and provided with a thread extending from a thread clamp tothe adjacent salvage and having a second thread extending from a shuttleon the support, relatively strong spring means to hold the cutter inforward closed position relatively to the cutter means, relatively weakspring means tendingto move the cutter to rearward open positionrelatively to the cutter means and normally overpowered by therelatively strong spring means, a stop for the cutter to limit rearwardmotion of the latter, and means connecting the lay to the relativelystrong means to move the latter rearwardly during the backward stroke ofthe lay, whereupon the relatively weak spring means moves the cutter torearward open position against said stop behind the first thread and infront of the second thread, the relatively strong spring means movingthe cutter forwardly when the lay moves forwardly from the rearmostposition thereof and overpowering the relatively weak spring means toreturn the cutter to normal closed forward position to cut the thread.

3. In a thread cutter for a loom having a layv stop means on the supportentering the slot'and constituting with the latter a sliding and rockingconnection between the cutter and the support, a relatively strongspring connected to the cutter to move the latter forwardly with respectto the support, a weaker spring connected to the cutter and tending tomove the latter rearwardly,

rearwardly, whereupon the weaker spring causes the cutter to moverearwardly by a. relative motion between the slot and said guide andstop means followed by an upward pivotal motion of the cutter withrespect to the support caused by engagement of the guide and stop meanswith the forward end of the slot in said cutter toopen the latter in aposition behind the first named thread, the stronger spring actingduring the following forward motion of the lay to move the cutterpivotally with respect to the support in a downward direction behindsaid thread and thereafter move the cutter with a substantiallyhorizontal forward sliding motion relatively to the support to move thecutter to closed position relatively to the cutter means to out saidthread.

5. In a thread cutter for looms having a lay reciprocating betweenfrontand back center positions and provided with a thread extending from athread clamp to the adjacent selvage,a normally stationary supportmounted in front of the lay, cutter means mounted on the support, asecond cutter mounted on the support for movement relative thereto, twoopposed springs one of which is stronger than the other and tendsnormally to hold the second cutter in forward closed position relativelyto the first cutting means, the other of said springs tending to movethe second cutter to rearward open position relative to the first cuttermeans, connections between the stronger spring and the lay to overpowersaid stronger spring during backward motion of the lay, whereupon theweaker spring moves the second cutter rearwardly, guide means for thesecond cutter to cause said weaker spring to move the second cutterrearwardly in a substantially horizontal direction against the thread tobend the latter and thereafter cause said weaker spring to raise thesecond cutter to a point above and rearwardly of and out of engagementwith the thread, said stronger spring thereafter operative duringforward motion of the lay to overpower the weaker spring and cooperatewith the guide means .to move the second cutter downwardly to a positionbehind the thread and then forwardly to closed position relatively tothe first cutter means to out said thread.

6. In a thread cutter for a loom having a lay reciprocating betweenfront and back center positions and provided with a thread extendingfrom a thread clamp to the adjacent selvage, a normally stationarysupport mounted in front of the lay, cutter means mounted on thesupport, a second cutter mounted on the support for movement relativelythereto, means defining a sliding and rocking connection between thesecond cutter and the support and limiting rearward motion of the secondcutter relatively to the su port, two springs connected to the supportacting in opposite directions on the second cutter, one of said springsbeing stronger than the other spring and acting to hold the secondcutter in forward closed position relatively to the first cutter means,the other spring tending to move the second cutter rearwardly andcooperate with said means to move the second cutter to open positionrelatively to the first cutter means, and connections between the layand the stronger spring effective during rearward motion of the lay tomove the stronger spring rearwardly out of controlling positionrelatively to the second cutter, whereupon said other spring cooperateswith the sliding and rocking connection to move the second cutterrearwardly in a substantially horizontal direction by reason of thesliding feature of said connection to a position against the thread tobend the latter rearwardiy and then rock said second cutter upwardly byreason of the rocking feature of said connection to a position above andto the rear of and out of engagement with said thread when the lay is inrearward position, the stronger spring operative during the followingforward motion of the lay to cooperate with the rocking feature of saidconnection to move the second cutter downwardly against the action ofsaid other spring to a position behind the thread and then forwardly incooperation with the sliding feature of said connection to closedposition relatively to the first cutter means to cut the thread as thelay moves forwardly.

7. In a thread cutter having a lay reciprocating between front and backcenter positions and provided with a thread extending from the threadclamp to the adjacent selvage, substantially fixed cutter means, acutter blade movable rearwardly from a closed cutting positionrelatively to the fixed cutting means, controller means for the cutterblade including two members acting to move the cutter blade in oppositedirections, one of said members being stronger than the other andconnected to the lay to be overpowered thereby during backward motion ofthe lay, said controller means also including a support for the cutterblade with respect to which the latter can have horizontal and upwardmotions, the weaker member cooperating with the support to move thecutter blade rearwardly against the thread to bend the latter rearwardlyand then raise the cutter blade to a position above and behind thethread out of contact with the latter as the lay moves rearwardly,whereupon the thread snaps back to its original position in front of thecutter blade, the stronger member thereafter cooperating with thesupport to move the cutter blade downwardly to a position behind thethread and then forwardly to closed position relatively to the cuttermeans as the lay advances.

ERNEST P. GUERIN.

